多分辨重叠变换在扩频通信系统抗干扰中的应用

Interference Excision in Spread Spectrum Communication Systems Using Hierarchical Lapped Transforms

本文利用多分辨重叠变换 (HLT)把接收机信号映射到变换域进行抗干扰处理 .与重叠变换 (LT)不同 ,HLT对信号频谱的非均匀划分可以有效地把干扰能量集中在有限的变换域子带 (TransformBins)中 ,因此对抑制随机脉冲干扰非常有效 .与小波变换 (WT)相比 ,HLT对信号频谱的划分更加灵活 .由于可以使用基于重叠变换的快速算法 ,在滤波性能相当的情况下 ,HLT比小波变换节省计算量 .仿真结果表明 ,其于HLT的变换域处理方案可以有效地抑制非时变窄带干扰和时变宽带干扰 ,明显地改善系统性能 .

In this paper,Hierarchical lapped transforms (HLT) are used to transform the received data signal to the transform domain wherein excision is performed.Unlike the lapped transforms(LT),HLT can effectively isolate the interference energy to a small number of bins in the transform domain by non uniform division of the signal spectrum.Comparied to the wavelet transforms(WT),HLT have more flexibility in dividing the signal spectrum.Moreover,we have the advantage of low computational complexity while not losing in filtering performance.Simulation results demonstrate that,transform domain excision technique based on HLT is capable of excising stationary narrow band interference and non stationary pulsed interference,thus significantly improving the system performance.